In general, in electronic devices, such as personal computers, a hard disk drive (HDD) is used as a storage device. The hard disk drive is a disk drive that stores data in a disk storage medium called a hard disk.
For the purpose of, for example, protection of the data stored in a disk storage medium, many disk drives and many electronic devices with disk drives have, for example, an HDD protection function of retracting a magnetic head to a safety position when impact (vibration) exerted on the electronic devices is detected. More specifically, the HDD protection function is a function of retracting the magnetic head to a safety position when the vibration exerted on the electronic device exceeds a predetermined threshold. The threshold is also called a sensitivity level, which is normally set manually by a user.
However, it is difficult for the user to determine which sensitivity level is appropriate to the current state of the electronic device, and therefore there is a demand for a new technique capable of overcoming this difficulty.